Copping a plea for 19 murders, a high-ranking Mafia turncoat offers testimony that may finally scrape the Teflon off Gambino boss John Gotti

With his stocky build, thick neck and gravelly voice, Salvatore Gravano lives up to his nickname, "Sammy the Bull." But as he said on the witness stand last week, his enemies are more likely to start calling him by a new moniker, "Sammy the Rat." In five days of often chilling testimony, the former Gambino family underboss calmly described the secret inner workings and rituals of La Cosa Nostra and provided gory details of the 19 killings he admitted taking part in. Most of all, he tried to hammer nails into the legal coffin of John Gotti, the head of the...